help please trying to conceive

Hello I'm 20 years old me and my bf has been trying last 3 month nothing. Happen well I had my piredo on July 1 2o12 and on the 26 witch is today when I wrote this I statred and I'm 3 days early befor my next one what could this mean I'm so lost and confused I've never been pregant befor in my life been trying any help with this